A Novel Sol–Gel Approach to Highly Condensed Silicas at Low Temperature

Abstract We have discovered new Meerwein’s reagent-catalyzed sol–gel polycondensations, which provide highly condensed silica Q4 and biphenylylene silica T3 as amorphous gels with marginal silanols starting from TEOS and 4,4′-bis(triethoxysilyl)biphenyl (BTEBph), respectively. We propose a plausible pathway for this protocol with possible silyloxonium intermediates.